openwrt/target/linux/brcm2708/patches-4.19/950-0134-net-lan78xx-Disable-TCP-Segmentation-Offload-TSO.patch
Koen Vandeputte 7533087565 kernel: bump 4.19 to 4.19.84
Refreshed all patches.

Altered patches:
- 950-0748-net-bcmgenet-Workaround-for-Pi-4B-network-issue.patch
- 950-0754-Revert-net-bcmgenet-Workaround-for-Pi-4B-network-iss.patch
- 902-debloat_proc.patch

Remove upstreamed:
- 150-MIPS-bmips-mark-exception-vectors-as-char-arrays.patch

New symbols:
X86_INTEL_MPX
X86_INTEL_MEMORY_PROTECTION_KEYS
X86_INTEL_TSX_MODE_OFF
X86_INTEL_TSX_MODE_ON
X86_INTEL_TSX_MODE_AUTO

Compile-tested on: cns3xxx, x86_64
Runtime-tested on: cns3xxx

Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
2019-11-19 14:59:03 +01:00

57 lines
2.1 KiB
Diff

From 59555269e09f06ae0ded9007c4aa02fa55ce71ca Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.org>
Date: Wed, 13 Jun 2018 15:21:10 +0100
Subject: [PATCH 134/806] net: lan78xx: Disable TCP Segmentation Offload (TSO)
TSO seems to be having issues when packets are dropped and the
remote end uses Selective Acknowledge (SACK) to denote that
data is missing. The missing data is never resent, so the
connection eventually stalls.
There is a module parameter of enable_tso added to allow
further debugging without forcing a rebuild of the kernel.
https://github.com/raspberrypi/linux/issues/2449
https://github.com/raspberrypi/linux/issues/2482
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
---
drivers/net/usb/lan78xx.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -439,6 +439,15 @@ static int msg_level = -1;
module_param(msg_level, int, 0);
MODULE_PARM_DESC(msg_level, "Override default message level");
+/* TSO seems to be having some issue with Selective Acknowledge (SACK) that
+ * results in lost data never being retransmitted.
+ * Disable it by default now, but adds a module parameter to enable it for
+ * debug purposes (the full cause is not currently understood).
+ */
+static bool enable_tso;
+module_param(enable_tso, bool, 0644);
+MODULE_PARM_DESC(enable_tso, "Enables TCP segmentation offload");
+
static int lan78xx_read_reg(struct lan78xx_net *dev, u32 index, u32 *data)
{
u32 *buf = kmalloc(sizeof(u32), GFP_KERNEL);
@@ -3006,8 +3015,14 @@ static int lan78xx_bind(struct lan78xx_n
if (DEFAULT_RX_CSUM_ENABLE)
dev->net->features |= NETIF_F_RXCSUM;
- if (DEFAULT_TSO_CSUM_ENABLE)
- dev->net->features |= NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_SG;
+ if (DEFAULT_TSO_CSUM_ENABLE) {
+ dev->net->features |= NETIF_F_SG;
+ /* Use module parameter to control TCP segmentation offload as
+ * it appears to cause issues.
+ */
+ if (enable_tso)
+ dev->net->features |= NETIF_F_TSO | NETIF_F_TSO6;
+ }
if (DEFAULT_VLAN_RX_OFFLOAD)
dev->net->features |= NETIF_F_HW_VLAN_CTAG_RX;